symboom
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Oxygen gas from the hypochlorite ion and catalyst
So I have been reacting sodium hypochlorite
With transition metal salts
Copper sulfate forms apple green copper oxychloride
No oxygen produced
Same with calcium hypochlorite makes two percipitates
Nickel sulfate is reacted with sodium hypochlorite
Black percipitate is formed and oxygen is formed
The problem is when one mixes calcium hypochlorite with nickel chloride convered the sulfate to the chloride with calcium chloride
Same with nickel sulfate black percipitate forming
I think its forming chlorine gas
2NaClO + NiSO4 --> Ni2O3 + Na2SO4 + O2 + NaCl
Ca(ClO)2 + NiSO4 -->> Ni2O3 + CaSO4 + Cl2 + H2O
I know its not balanced but here is what I thing is going on
Although the smell could be coming from the compound
[Edited on 10-12-2016 by symboom]
[Edited on 10-12-2016 by symboom]
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j_sum1
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I don't know about Ni, but I know that cobalt chloride acts as a catalyst to liberate O from bleach. (Interestingly, gas evolution with CoSO4 was not
evident.)
Anyway, it surprises me little that other transition metals behave in the same way.
I would check your copper reaction carefully while you are at it. Are you certain it is copper oxychloride? (Cu2(OH)3Cl) It seems to me that some
chlorines have gone missing in that equation.
This sounds like a pretty fun sort of an investigation.
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symboom
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I bought nickel sulfate I did not know this reaction occurs
Later just bought cobalt nitrate apparently does the same reaction have not tried it yet but probally going to do side by side comparison with cobalt
and nickel
Wish the would nickel would energetically decompose the
Calcium hypochlorite which is a more concentrated hypochlorite form.
https://en.m.wikipedia.org/wiki/Cobalt(III)_oxide
Also tried with zinc same as the copper
Both copper and zinc seem to just make oxychlorides
This is all from just observation I could not find anywhere this experiment has been performed
Thanks you for your response
[Edited on 10-12-2016 by symboom]
[Edited on 10-12-2016 by symboom]
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symboom
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This video of copper sulfate and sodium hypochlorite
Forming copper hypochlorite for the post above
https://m.youtube.com/watch?v=tdkhHAiGWgQ&t=9s
______________________________________
Sodium Hypochlorite
Decomposition to chlorate or oxygen
If I'm reading correctly
<---chlorine--4pH---oxygen----6pH----chlorate--10pH----oxygen--->
Competition of the two possible reactions
In hot sodium hypochlorite solutions, the reaction competes between chlorate formation and yielding sodium chloride and/or sodium chloride and oxygen
gas production depending on pH levels and added catalysis.
The oxygen pathway predominates at pH 10.
This decomposition is affected by light and metal ion catalysts such as in increasing activity from weak catalytic to strongest copper, nickel,
cobalt, and iridium.
References
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5666953/
https://en.m.wikipedia.org/wiki/Sodium_hypochlorite
These two decomposition reactions of NaClO solutions are maximized at pH around 6
Chlorate
This reaction occurs in sodium hypochlorite solutions at high temperatures, forming sodium chlorate and sodium chloride
This reaction is used in the production of sodium chlorate.
Catalysts like sodium dichromate and sodium molybdate may be added industrially to reduce the oxygen pathway, but a report claims that only the latter
is effective
The chlorate-producing reaction predominates at pH above 6
Oxygen
An alternative decomposition of hypochlorite produces oxygen instead:
The oxygen one becomes significant below that pH. For example, at 80 °C, with NaOCl and NaCl concentrations of 80 mM, and pH 6–6.5, the chlorate
is produced with ∼95% efficiency.
Catalysts
The addition of chloride salts of cobalt and iridium showed catalytic effects on oxygen formation. The addition of iridium chloride also catalyzed the
formation of chlorate with increasing selectivity for chlorate with increasing pH.
[Edited on 31-7-2020 by symboom]
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